Pass value and use std::move instead of const reference for ack listeners.

net/quic/core/quic_spdy_stream.h

Index: net/quic/core/quic_spdy_stream.h
diff --git a/net/quic/core/quic_spdy_stream.h b/net/quic/core/quic_spdy_stream.h
index 27d3de68831ebc7fbf89e8ff47efe32217a55e35..783f2b1c42e40aeb27797881edb875f14101d1e5 100644
--- a/net/quic/core/quic_spdy_stream.h
+++ b/net/quic/core/quic_spdy_stream.h
@@ -105,19 +105,19 @@ class QUIC_EXPORT_PRIVATE QuicSpdyStream : public QuicStream {
   virtual size_t WriteHeaders(
       SpdyHeaderBlock header_block,
       bool fin,
-      const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate);
+      scoped_refptr<QuicAckListenerInterface> ack_notifier_delegate);
 
   // Sends |data| to the peer, or buffers if it can't be sent immediately.
   void WriteOrBufferBody(
       const std::string& data,
       bool fin,
-      const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate);
+      scoped_refptr<QuicAckListenerInterface> ack_notifier_delegate);
 
   // Writes the trailers contained in |trailer_block| to the dedicated
   // headers stream. Trailers will always have the FIN set.
   virtual size_t WriteTrailers(
       SpdyHeaderBlock trailer_block,
-      const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate);
+      scoped_refptr<QuicAckListenerInterface> ack_notifier_delegate);
 
   // Marks the trailers as consumed. This applies to the case where this object
   // receives headers and trailers as QuicHeaderLists via calls to
@@ -201,8 +201,7 @@ class QUIC_EXPORT_PRIVATE QuicSpdyStream : public QuicStream {
       QuicIOVector iov,
       QuicStreamOffset offset,
       bool fin,
-      const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate)
-      override;
+      scoped_refptr<QuicAckListenerInterface> ack_notifier_delegate) override;
 
  private:
   friend class test::QuicSpdyStreamPeer;